Auto Air Conditioning & Heater Repair: a/c 93 chevy 2500

Question
QUESTION: a/c was working great last night today compressor wont engage at all no evidence of leaks.what do i check next?

ANSWER: Get me some pressures check your cycling switch if you have refrigerant it should work.  Let me know what you find and I'll help.

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QUESTION: thank you sir for helping.i am not stupid but i don't know what you do.where can i find diagrams to find all items in system such as recycling switch, orifice tube, pressure check points and so on.what pressures should be and many things i'm not saying.i can do this only w/help.thanks so.  

Answer
You will need to get a manifold gauge set installed  to check the pressures.  If you do not have one then go to a mechanic and have him get you the pressures.  Your cycling switch is on the accumulator at the fire-wall this switch should have power going and out when you have enough refrigerant is the system.  If the system has no refrigerant then the switch will not let the compressor come on.